Answer: 230.697
Step-by-step explanation:
Answer:
14, 28, 42, 56, and 70 are the first 5 common multiples of 14
20, 40, 60, 80, and 100 are the first 4 common multiples of 20
Answer:
10%
Step-by-step explanation:
Percent change= New-Old |Old|× 100% percent change=81-90 |90| × 100= -9 90×100=-10%
Answer:
The ordered pair (1, 2) is a solution to the system of linear equations.
Answer:
Step-by-step explanation:
We want to determine a 90% confidence interval for the mean amount of time that teens spend online each week.
Number of sample, n = 41
Mean, u = 43.1 hours
Standard deviation, s = 5.91 hours
For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes
43.1 ± 1.645 × 5.91/√41
= 43.1 ± 1.645 × 0.923
= 43.1 ± 1.52
The lower end of the confidence interval is 43.1 - 1.52 =41.58
The upper end of the confidence interval is 43.1 + 1.52 =44.62
Therefore, with 90% confidence interval, the mean amount of time that teens spend online each week is between 41.58 and 44.62
